During the manufacturing and conversion processes associated with paper, plastic, fabrics, and various textiles, the finished products are wound into rolls for ease of handling and shipping to various converting operations, as well as to end users and consumers in some instances. The materials are wound on tubes or cores of cardboard or a similar material which have a hollow center portion. During shipping and handling of the rolls the ends of the tubes are plugged with devices, commonly called core plugs, which prevent damage to the ends of the tubes. Any damage to the ends of the tubes could render the roll unusable because it would prevent the insertion of centers or chucks (into the hollow internal bore of the tube) which are used for unwinding the product for use or conversion. These plugs are constructed of various materials, such as wood, plastic, resin bonded fiber, or resin bonded wood products. The materials used for construction are not particularly important for the purposes of this invention. While there is a wide variety of shapes and designs used for this purpose, all of them are of basic cylindrical or conical design in order to fill the end portion of the tubes completely and to prevent the plugs from falling out of the tubes.
Many customers of the manufacturing and converting operations require that rolls of narrow-width products be packaged together for ease of handling. These packages of narrow web rolls present a very unique handling problem due to the inherent instability in their axial direction as a result of extreme ratios of height to width. This instability results in the breakdown of the packages during normal conveyance of the rolls during their production and conversion into a shippable product. The individual rolls are subject to overturning and deformation. They are also very difficult to hold in a unit with adjacent rolls during formation of packages from individual rolls.
Because rolls are wound on a hollow core or tube, the tube becomes the basic building block used to tie adjunctly positioned rolls into a unitized package. Current industry practice consists of positioning like diameter rolls together, axially aligned, and then inserting another hollow tube (with dimensions adequate to reach through the entire package, but not protruding from the end rolls of the package) of smaller diameter through the tube on which the material is wound. The extreme ends of the tubes on which the outer rolls are wound are then plugged to prevent crushing or damage to the ends of the tubes on which the paper is wound. This in turn prevents the inner tube from falling out of the package and thus allows the package to be transported as a unit. This, however, does not prevent the package from breaking down because the rolls are not clamped or held together axially.